Green manufacturing is increasingly becoming popular, especially in lubricant manufacturing, as more environmentally friendly substitutes for mineral base oil and synthetic additives are being found among plant extracts and progress in methodologies for extraction and synthesis is being made. It has been observed that some of the important performance characteristics need enhancement, of which nanoparticle addition has been noted as one of the effective solutions. However, the concentration of the addictive that would optimised the performance characteristics of interest remains a contending area of research. The research was out to find how the concentration of green synthesized aluminum oxide nanoparticles in nano lubricants formed from selected vegetable oils influences friction and wear. A bottom-up green synthesis approach was adopted to synthesize aluminum oxide (Al2O3) from aluminum nitrate (Al(NO3)3) precursor in the presence of a plant-based reducing agent—Ipomoea pes-caprae. The synthesized Al2O3 nanoparticles were characterized using TEM and XRD and found to be mostly of spherical shape of sizes 44.73 nm. Al2O3 nanoparticles at different concentrations—0.1 wt%, 0.3 wt%, 0.5 wt%, 0.7 wt%, and 1.0 wt%—were used as additives to castor, jatropha, and palm kernel oils to formulate nano lubricants and tested alternately on a ball-on-aluminum (SAE 332) and low-carbon steel Disc Tribometer. All the vegetable-based oil nano lubricants showed a significant decrease in the coefficient of friction (CoF) and wear rate with Ball-on-(aluminum SAE 332) disc tribometer up to 0.5wt% of the nanoparticle: the best performances (eCOF = 92.29; eWR = 79.53) came from Al2O3-castor oil nano lubricant and Al2O3-palm kernel oil; afterwards, they started to increase. However, the performance indices displayed irregular behaviour for both COF and Wear Rate (WR) when tested on a ball-on-low-carbon steel Disc Tribometer.
Improving the practical skills of Science, Technology, Engineering and Mathematics (STEM) students at a historically black college and university (HBCU) was done by implementing a transformative teaching model. The model was implemented on undergraduate students of different educational levels in the Electrical Engineering (EE) Department at HBCU. The model was also extended to carefully chosen high and middle schools. These middle and high school students serve as a pipeline to the university, with a particular emphasis on fostering growth within the EE Department. The model aligns well with the core mission of the EE Department, aiming to enhance the theoretical knowledge and practical skills of students, ensuring that they are qualified to work in industry or to pursue graduate studies. The implemented model prepares students for outstanding STEM careers. It also increases enrolment, student retention, and the number of underrepresented minority graduates in a technology-based workforce.
In Nigeria, deforestation has led to an unimaginable loss of genetic variation within tree populations. Regrettably, little is known about the genetic variation of many important indigenous timber species in Nigeria. More so, the specific tools to evaluate the genetic diversity of these timber species are scarce. Therefore, this study developed species-specific markers for Pterygota macrocarpa using state-of-the-art equipment. Leaf samples were collected from Akure Forest Reserve, Ondo State, Nigeria. DNA isolation, quantification, PCR amplification, gel electrophoresis, post-PCR purification, and sequencing were done following a standardized protocol. The melting temperatures (TM) of the DNA fragments range from 57.5 ℃to 60.1 ℃ for primers developed from the MatK gene and 58.7 ℃ to 60.5 ℃ for primers developed from the RuBisCo gene. The characteristics of the ten primers developed are within the range appropriate for genetic diversity assessment. These species-specific primers are therefore recommended for population evaluation of Pterygota macrocarpa in Nigeria.
The Guangdong-Macao Intensive Cooperation Zone in Hengqin (Intensive Cooperation Zone) has emerged as a pivotal economic hub, attracting Macao residents and enterprises. However, disparities in contract-related rules between the zone and Macao have led to legal challenges. This article delves into a comparative study of contract laws between the People’s Republic of China (PRC) and Macao. Analyzing key facets such as pacta sunt servanda, freedom of contract, principle of equity, contract form, principles of interpretation, and termination of contract, the study identifies nuanced differences. Recognizing the imperative of aligning contract laws for the Intensive Cooperation Zone’s development, the article advocates for a unified legal environment. To achieve this, the author proposes a model contract law that prioritises the United Nations Convention on Contracts for the International Sale of Goods (CISG) as the basis. Notably, Macao’s contract-related rules should govern aspects not covered by the CISG given the policy trend in the Intensive Cooperation Zone. The proposed model law serves as a foundation for legislative reform, aiming to address the existing disparities and promote the Intensive Cooperation Zone’s economic growth.
Background: The background and objectives of the research revolve around bureaucracy as a classic form of the modern division of labor, with Max Weber acknowledging its inevitability. However, the objective implications of the bureaucracy’s iron cage are evident in governance and management experiences. The mayors of Tehran’s districts exemplify how Iranian culture interacts with bureaucracy. This research seeks to establish principles and governance for district governors using an alternative bureaucracy, parallel to conventional bureaucracy. Methods: The methods employed include twenty strategically selected interviews, considering age, municipal area, and work experience for maximum variance. Grounded theory methodology, specifically the approach by Anselm Strauss and Barney Glaser, guides the research, employing open coding, axial coding, and selective coding. MaxQDA 2020 software enhances the qualitative data analysis, facilitating organization, coding, and collaboration within the research team. Results: Findings indicate “inevitable violations” as a common starting point for interviewees, leading to three axes: “preconditions,” “objectives,” and “strategies and mechanisms” of alternative bureaucracy. In conclusion, breaking through bureaucracy becomes necessary for governors to act. Alternative bureaucracy, rooted in experience yet considering the bureaucratic field, requires transcendent goals. Hybridity and ethical principles are crucial when transitioning from conventional bureaucracy to the alternative in urban governance.
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